Maternal lithium and neonatal Ebstein's anomaly: evaluation with cross-sectional echocardiography

Lithium during pregnancy and after delivery: a review

Lithium is an effective treatment in pregnancy and postpartum for the prevention of relapse in bipolar disorder. However, lithium has also been associated with risks during pregnancy for both the mother and the unborn child. Recent large studies have confirmed the association between first trimester lithium exposure and an increased risk of congenital malformations. Importantly, the risk estimates from these studies are lower than previously reported. Tapering of lithium during the first trimester could be considered but should be weighed against the risks of relapse. There seems to be no association between lithium use and pregnancy or delivery related outcomes, but more research is needed to be more conclusive. When lithium is prescribed during pregnancy, lithium blood levels should be monitored more frequently than outside of pregnancy and preferably weekly in the third trimester. We recommend a high-resolution ultrasound with fetal anomaly scanning at 20 weeks. Ideally, delivery should take place in a specialised hospital where psychiatric and obstetric care for the mother is provided and neonatal evaluation and monitoring of the child can take place immediately after birth. When lithium is discontinued during pregnancy, lithium could be restarted immediately after delivery as strategy for relapse prevention postpartum. Given the very high risk of relapse in the postpartum period, a high target therapeutic lithium level is recommended. Most clinical guidelines discourage breastfeeding in women treated with lithium. It is highly important that clinicians inform and advise women about the risks and benefits of remaining on lithium in pregnancy, if possible preconceptionally. In this narrative review we provide an up-to-date overview of the literature on lithium use during pregnancy and after delivery leading to clinical recommendations.

Lithium Use in Pregnancy and the Risk of Cardiac Malformations

BACKGROUND

There has been concern that exposure to lithium early in pregnancy may be associated with a marked increase in the risk of Ebstein's anomaly (a right ventricular outflow tract obstruction defect) in infants and overall congenital cardiac defects, but data are conflicting and limited.

METHODS

We conducted a cohort study involving 1,325,563 pregnancies in women who were enrolled in Medicaid and who delivered a live-born infant between 2000 and 2010. We examined the risk of cardiac malformations among infants exposed to lithium during the first trimester as compared with unexposed infants and, in secondary analyses, with infants exposed to another commonly used mood stabilizer, lamotrigine. Risk ratios and 95% confidence intervals were estimated with control for psychiatric and medical conditions, medications, and other potential confounders.

RESULTS

Cardiac malformations were present in 16 of the 663 infants exposed to lithium (2.41%), 15,251 of the 1,322,955 nonexposed infants (1.15%), and 27 of the 1945 infants exposed to lamotrigine (1.39%). The adjusted risk ratio for cardiac malformations among infants exposed to lithium as compared with unexposed infants was 1.65 (95% confidence interval [CI], 1.02 to 2.68). The risk ratio was 1.11 (95% CI, 0.46 to 2.64) for a daily dose of 600 mg or less, 1.60 (95% CI, 0.67 to 3.80) for 601 to 900 mg, and 3.22 (95% CI, 1.47 to 7.02) for more than 900 mg. The prevalence of right ventricular outflow tract obstruction defects was 0.60% among lithium-exposed infants versus 0.18% among unexposed infants (adjusted risk ratio, 2.66; 95% CI, 1.00 to 7.06). Results were similar when lamotrigine-exposed infants were used as the reference group.

CONCLUSIONS

Maternal use of lithium during the first trimester was associated with an increased risk of cardiac malformations, including Ebstein's anomaly; the magnitude of this effect was smaller than had been previously postulated. (Funded by the National Institute of Mental Health.).

Current Trends in the Management of Neonates With Ebstein's Anomaly

BACKGROUND

The optimal management strategy for neonates with Ebstein's anomaly is unknown. This analysis was undertaken to assess current trends in the management and prognosis of neonates born with Ebstein's anomaly in the United States, as reflected in an administrative database.

METHODS

The Pediatric Health Information System database (40 children's hospitals) was used to review the reported incidence and available data on neonates with Ebstein's anomaly treated in the United States between 2003 and 2007. Primary outcome was hospital survival. Of the 415 patients identified, 257 (62%) did not undergo initial surgical intervention as neonates. Aortopulmonary shunt only was done on 63 patients (15%), single-ventricle palliation on 36 (9%), two-ventricle repair on 16 (4%), heart transplantation in 3 (1%), and a catheter-based intervention or a hybrid palliative approach was applied in 40 (10%). Intergroup comparisons were done using chi-square analyses.

RESULTS

Mortality for the entire cohort was 24% (100 of 415). For medically treated patients, this was 22% (56 of 257). For surgically treated and hybrid patients, this was 30% and 23%, respectively (P = NS).

CONCLUSIONS

The majority of patients born with Ebstein's anomaly currently do not undergo surgical intervention as neonates. Significant early mortality in this group suggests that certain subsets of patients may benefit from earlier surgical intervention. Among the severely symptomatic neonates who do undergo early surgical intervention, the mortality remains high, irrespective of the surgical approach taken. A multicenter trial may be appropriate to identify strategies to optimize care for these critically ill neonates. Further analysis of risk factors for early mortality is warranted.

Lithium in pregnancy: the need to treat, the duty to ensure safety

INTRODUCTION

Untreated bipolar disorder during pregnancy leads to detrimental repercussions on the mother-infant pair's health. Despite different drugs having been proposed as mood stabilizers, lithium remains the first-choice agent for preventing mood changes.

AREAS COVERED

Analyzing up-to-date information on the reproductive safety of lithium and providing practice guidelines to optimize its use during pregnancy.

EXPERT OPINION

Findings from prospective and case-control studies confirm an increased, specific risk of Ebstein's anomaly (4.45-7.6/1000 live births), although lower than that previously reported. A potential increase in the risk of neural tube defects should also be taken into consideration. Moreover, several perinatal complications may occur, and even in the presence of relatively low infant serum levels, in the case of drug exposure during late pregnancy. Despite such concerns, lithium should still be considered the first-choice agent for treating bipolar disorder in pregnancy. Indeed, the U.S. FDA recently issued a new warning regarding the reproductive safety of antipsychotics. Moreover, the risk of fetal valproate/carbamazepine syndrome (and the confirmed neurodevelopmental teratogenicity of valproate) contraindicates the use of both medications, whereas the use of lamotrigine is limited by efficacy concerns. However, women who need lithium treatment during pregnancy should be carefully monitored: a strict gynecologic and psychiatric surveillance and, probably, preconception folate supplementation is highly advisable. Moreover, delivery should be programmed in Neonatal Intensive Care Units to ensure optimal management of potential iatrogenic perinatal complications.

Neonatal toxicity and transient neurodevelopmental deficits following prenatal exposure to lithium: Another clinical report and a review of the literature

I report the case of an infant girl who was exposed to lithium during gestation and her follow-up at the age of 1 year. She presented with transient neurodevelopmental deficits including lethargy, hypotonia, and poor oral feeding ability in the neonatal period. She required supportive treatment and made gradual improvement in neurologic functioning. On examination at the age of 1 year, physical findings and psychomotor development were normal. The English literature from 1978 to 2004 is reviewed. A total of 30 patients who were exposed to lithium during gestation with adequate clinical description were identified. A significant number of these babies presented with neurodevelopmental deficits and depressed neurological status including hypotonia, respiratory distress syndrome, cyanosis, lethargy, and weak suck and Moro reflexes in the neonatal period. The majority of these abnormalities resolved and most babies made full recovery. Other abnormalities were structural as well as functional involvement of the cardiovascular system, macrosomia, prematurity, jaundice, diabetes insipidus, and involvement of the thyroid gland. While the use of lithium during pregnancy does not appear to significantly increase the risk of congenital anomalies, it is frequently associated with perinatal complications and reversible neonatal toxicity. Suggested guidelines for appropriate monitoring of infants and breast-feeding of exposed babies are presented. In addition, prenatal surveillance of women with bipolar disorders who are being treated with lithium is briefly discussed.

Case report and review of the perinatal implications of maternal lithium use

The purpose of this study was to review the use of lithium in pregnancy and its effects on the neonate. This was a case study and review of the published literature. Lithium is commonly used in the treatment of psychiatric disorders, specifically bipolar depression. Bipolar disorders that require treatment with lithium demand special consideration when the woman becomes pregnant. Reported neonatal problems with maternal lithium therapy include Ebstein's anomaly, poor respiratory effort and cyanosis, rhythm disturbances, nephrogenic diabetes insipidus, thyroid dysfunction, hypoglycemia, hypotonia and lethargy, hyperbilirubinemia, and large-for-gestational-age infants. Lithium can have adverse effects on the fetus and newborn infant, but data suggest normal behavioral patterns in childhood.

Prospective multicentre study of pregnancy outcome after lithium exposure during first trimester

Lithium carbonate is an effective drug for prophylaxis and treatment of major affective disorders. In-utero exposure to lithium during the first trimester of pregnancy might be associated with an increased risk of cardiac malformations, especially the rare Ebstein's anomaly. We prospectively recruited and followed 148 women (mean age 30 years, SD 5 range 15-40) using lithium during the first trimester of pregnancy, who consulted four teratogen information centres in the USA and Canada. Pregnancy outcome was compared with that of controls matched for maternal age. We had complete follow-up of pregnancy outcome in 138 of 148 patients recruited. In the other 10, fetal echocardiograms were available but postnatal follow-up was not done. Mean daily dose of lithium was 927 mg (SD 340). Rates of major congenital malformations did not differ between the lithium (2.8%) and control (2.4%) groups. 1 patient in the lithium group chose to terminate pregnancy after Ebstein's anomaly was detected by a prenatal echocardiogram. There was 1 ventricular septal defect in the controls. Birthweight was significantly higher in the lithium-exposed infants than in the controls despite identical gestational ages (3475 [660] g vs 3383 [566] g, p = 0.02). The true difference in birthweight might have been even larger, since significantly more women using lithium than controls were cigarette smokers (31.8% vs 15.5%, p = 0.002). These results indicate that lithium is not an important human teratogen. Women with major affective disorders who wish to have children may continue lithium therapy, provided that adequate screening tests, including level II ultrasound and fetal echocardiography, are done.

Teratogenic activity of lithium carbonate: an experimental update

The teratogenic potential of lithium carbonate was re-examined using mouse embryos as an experimental model. Externally it was found that, like many other psychoactive drugs, it exhibits a teratogenic activity that is confined to the development of the central nervous system. When administered intraperitoneally to pregnant females in doses ranging from 330 to 340 mg/kg at the very beginning of the ninth gestation day, i.e., during the critical period of the neural tube closure, it is embryotoxic, causes retardation of development, and induces the "neurotropic syndrome of malformations" comprising exencephaly, craniorachischisis, rachischisis, kinking of the spinal cord, and dilation of the fourth brain ventricle. Depending on the exact time of gestation when lithium carbonate is administered, the frequencies of exencephaly and spinal kinking after treatment 1 hour into the ninth day are compared with those after treatment 2 or 3 hours into the ninth day, incidence of exencephaly is increased at the later time and the incidence of spinal kinking is decreased.